Mailing lists and discussion groups are becoming increasingly popular and contain potentially useful information. Finding relevant information in such mailing lists or discussion groups, however, is generally quite difficult, since they generally provide little information about the information that is discussed in a given email thread. Thus, users are generally required to read most of the postings in a given thread to gain an understanding of the content. Typically, mailing list archives are represented as a sequence of the threads in the archive, where each thread is shown as an indented list with subject lines and related information, such as the name of the sender, the time of posting and the number of follow-ups for the message. Even when the subject of the initial posting (root) of the thread is well chosen and informative, the indented representation is generally not very helpful since the subjects of all follow-up messages simply repeat the original subject.
A hierarchical listing of such archives provides a first level representation containing the subject of the first email in each thread (the root email) and the number of postings in the thread. When a user selects a particular thread or subject, the second level representation of the selected thread is shown in a new window where the messages can be opened and viewed one at a time. The introduction of this second level allows the user to quickly skim through the initial subject lines and determine if there is a topic of interest to read. Even when the subject for the initial posting is well-chosen, however, it can rarely give the user a good description of what is being discussed.
Google groups further improve on such hierarchical listings by using a two-level representation. The first level is similar to the first level in the hierarchical listings and indicates the date of posting, the subject of initial email in the thread, the name of the most recent poster and the number of messages in the thread. The second level consists of a two frame page showing the indented structure and a digest of the messages on one screen. The digest consists of the concatenated bodies of the first ten messages posted in the thread. While the representation employed by Google groups allows a user to more easily find topics of interest, the user must still browse the digests containing actual content of each thread.
A need therefore exists for methods and apparatus for generating thread overviews that serve as indicative summaries for the thread. A further need exists for a more efficient representation that allows a user to determine which threads to read without browsing the actual content of the thread.